It turns out Norah and Jonah are not mother and son but twin sisters.

Suddenly, Nathan's consciousness is ripped away from the Rhodesia lodge, and he finds himself face to face with Lady Grayer and another woman. The hallucinations only become more vivid after the boys enter the house until all vestiges of the 'reality' of Slade House are replaced by visions of Nathan's father's lodge in Rhodesia. But as the hallucinations become more real and all-encompassing, Nathan realizes that something else is afoot. Nathan begins to suffer intense hallucinations which he initially attributes to the Valium. Bishop and Lady Grayer remain in the house, the two boys entertain themselves in the garden. Nathan-after popping a Valium he stole from his mother's purse-promptly pairs off with Grayer's son, Jonah. In 'The Right Sort,' young Nathan Bishop and his mother visit Slade House, an estate belonging to the esteemed noblewoman Lady Norah Grayer. The book is divided into five parts which each take place during a different decade: 'The Right Sort' in 1979, 'Shining Armor' in 1988, 'Oink Oink' in 1997, 'You Dark Horse You' in 2006, and 'Astronauts' in 2015. The book tells the story of various mysterious events occurring over a thirty-five year period at an estate known as Slade House. His seventh book, Slade House is an expanded version of a story Mitchell originally wrote on Twitter.

Slade House is a mystery-horror novel published in 2015 by the British novelist David Mitchell.

David mitchell author slade house